Sustained release formulations of dysoxylum binefacterum

Abstract

The present invention relates to the novel formulation for sustained or delayed release of rohitukine-rich Dysoxylum binectariferum extract/fraction and a process for preparing the same wherein the extract is wet-granulated using excipients i.e. biodegradable polymers and/or non-biodegradable polymers alone or in combination, and the said granules are either filled into a capsule or compressed into a tablet. The said formulation comprising a granulated extract/fraction of rohitukine-rich Dysoxylum binectariferum with polymers has resulted in a sustained release of the extract or fraction over a period of 16-24 hrs. The said formulations are useful in the treatment of inflammatory diseases.

We claim: 
     
       1. A sustained release formulation comprising granules, said granules comprising:
 30-60% w/w of an extract or fraction obtained from leaves of  Dysoxylum binectariferum;    
 25-50% w/w of hydroxypropylmethylcellulose; 
 5-15% w/w of sodium alginate; and 
 a binder; 
 wherein the extract or fraction comprises at least 2% w/w of Rohitukine and at least 1% w/w of Schumaniofioside A. 
 
     
     
       2. The sustained release formulation according to  claim 1 , wherein the extract is a hydroalcoholic extract. 
     
     
       3. The sustained release formulation according to  claim 1 , wherein the granules comprises a fraction obtained from leaves of  Dysoxylum binectariferum , and the fraction is a soluble portion of a methanol:acetone system of the extract. 
     
     
       4. The sustained release formulation according to  claim 1 , wherein the hydroxypropylmethylcellulose is hydroxypropylmethylcellulose K4M or hydroxypropylmethylcellulose K15M. 
     
     
       5. The sustained release formulation according to  claim 1 , wherein the hydroxypropylmethylcellulose is hydroxypropylmethylcellulose K15M. 
     
     
       6. The sustained release formulation according to  claim 1 , wherein a total in-vitro dissolution time of said formulation required for release of 60-100% of rohitukine is between 16-24 hours. 
     
     
       7. The sustained release formulation according to  claim 1 , wherein the binder is selected from the group consisting of polyvinylpyrrolidone K 30 and polyvinylpyrrolidone K15. 
     
     
       8. The sustained release formulation according to  claim 1 , wherein the said formulation is in the form of a hard gelatin capsule or a tablet. 
     
     
       9. The sustained release formulation according to  claim 1 , wherein a total in-vitro dissolution time of said formulation required for release of 88-100% of rohitukine is between 16-24 hours. 
     
     
       10. A sustained release formulation comprising granules, said granules comprising:
 30-60% w/w of an extract or fraction obtained from leaves of  Dysoxylum binectariferum;    
 25-50% w/w of hydroxypropylmethylcellulose; 
 5-15% w/w of sodium alginate; and 
 a binder; 
 wherein the extract or fraction comprises 2.6-13% w/w of Rohitukine and 0.5-10% w/w of Schumaniofioside A. 
 
     
     
       11. The sustained release formulation according to  claim 10 , wherein the granules comprise an extract obtained from leaves of  Dysoxylum binectariferum , the extract comprising 2.6-7.8% w/w of rohitukine and 0.55-5% w/w of schumaniofioside A. 
     
     
       12. The sustained release formulation according to  claim 10 , wherein the granules comprise a fraction obtained from leaves of  Dysoxylum binectariferum , the fraction comprising 5-13% w/w of rohitukine and 4-10% w/w of schumaniofioside A. 
     
     
       13. The sustained release formulation according to  claim 1 , wherein the formulation exhibits a rohithukine release half-life (T 50% ) of about 4 hours. 
     
     
       14. The sustained release formulation according to  claim 1 , wherein the formulation exhibits a T 75%  rohitukine release of about 8 to about 10 hours.